在 roar-rails 中创建嵌套资源的集合答案

【问题标题】：Creating a collection of nested resources in roar-rails在 roar-rails 中创建嵌套资源的集合
【发布时间】：2016-01-16 08:45:36
【问题描述】：

我正在尝试使用一组嵌套资源创建新对象。当我发布我的 json 时，我得到：

ActiveRecord::AssociationTypeMismatch: FormLabel(#70306552439440) expected, got Hash(#70306480154920)

这是我的代码：

# form.rb
class Form < ActiveRecord::Base
  has_many :form_labels
  validates_presence_of :name
end

# form_label.rb
class FormLabel < ActiveRecord::Base
  belongs_to :form
  validates_presence_of :form
  validates_presence_of :text
end

# form_representer.rb
module FormRepresenter
  include Roar::JSON
  property :id
  property :name
  collection :form_labels
end

# form_label_representer.rb
module FormLabelRepresenter
  include Roar::JSON
  property :text  
end

# form_controller.rb
class FormsController < ApplicationController
  include Roar::Rails::ControllerAdditions
  def create
    form = Form.new
    consume!(form)
    respond_with(form)
  end

当我调试时，这些是参数：

0> params
=> {"name"=>"Address", "form_labels"=>[{"text"=>"foo"}], "format"=>"json", "controller"=>"forms", "action"=>"create", "form"=>{"name"=>"Address"}}

错误是：

ActiveRecord::AssociationTypeMismatch: FormLabel(#70237358584300) expected, got Hash(#70237286721880)

【问题讨论】：

标签： ruby-on-rails json rails-roar

【解决方案1】：

错误在以下行：

collection :form_labels

必须是：

collection :form_labels, decorator: FormLabelRepresenter, class: FormLabel

见https://github.com/apotonick/roar-rails/issues/125#issuecomment-172175231

【讨论】：